Inflame desulfurization and denoxification of high sulfur containing fuels

ABSTRACT

A process for the preparation of a liquid fuel and resulting fuel including a sulfur and nitrogen capturing additive consisting essentially of Na + , Fe ++  and an element X selected from group consisting of Mg ++ , Ba ++ , Ca ++ , Li + , K +  and mixtures thereof wherein Na +  is present in an amount of less or equal to 40 wt. % based on the total weight of the water soluble additive Fe ++  is present in an amount of greater than or equal to 0.4 wt. % based on the total weight of the water soluble additive with the balance essentially element X wherein the ratio of Na +  and Fe ++  is about between 7.5:1.0 to 100:1.0.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is related to Application Ser. No. 133,327, filedconcurrently herewith and is a Continuation-In-Part of Application Ser.No. 014,871, filed Feb. 17, 1987 which in turn is a Continuation-In-Partof Application Ser. No. 875,450, filed June 17, 1986.

BACKGROUND OF THE INVENTION

The present invention relates to a process for the preparation of liquidfuels and the resulting fuel and, more particularly, a process thatallows a high sulfur and nitrogen containing fuel to be converted intoenergy by combustion with a substantial reduction in sulfur oxideemissions and nitrogen oxide emissions.

Low gravity, viscous hydrocarbons found in Canada, The Soviet Union,United States, China and Venezuela are normally liquid with viscositiesranging from 10,000 to 200,000 CP and API gravities of less than 12.These hydrocarbons are currently produced either by mechanical pumping,steam injection or by mining techniques. Wide-spread use of thesematerials as fuels is precluded for a number of reasons which includedifficulty in production, transportation and handling of the materialand, more importantly, unfavorable combustion characteristics includinghigh sulfur oxide emissions and unburned solids. To date, there are twocommercial processes practiced by power plants to reduce sulfur oxideemissions. The first process is furnace limestone injection whereinlimestone injected into the furnace reacts with the sulfur oxides toform solid sulfate particles which are removed from the flue gas byconventional particulate control devices. The cost for burning a typicalhigh sulfur fuel by the limestone injection method is between two tothree dollars per barrel and the amount of sulfur oxides removed by themethods is in the neighborhood of 50%. A more effective process forremoving sulfur oxides from power plants comprises flue gasdesulfurization wherein CaO+H₂ O are mixed with the flue gases from thefurnace. In this process 90% of the sulfur oxides are removed; howeverthe cost for burning a barrel of fuel using the process is between fourand five Dollars per barrel. Because of the foregoing, the high sulfurcontent, viscous hydrocarbons have not been successfully used on acommercial basis as fuels due to the high costs associated with theirburning.

It is well known in the prior art to form oil in water emulsions for useas a combustible fuel. See for example U.S. Pat. Nos. 4,114,015;4,378,230 and 4,618,348. In addition to the foregoing, the prior artteaches that oil in water emulsions formed from low gravity, viscoushydrocarbons can likewise be successfully combusted as a fuel. See forexample British Patent Specification No. 974,042 and U.S. Pat. No.4,618,348. The assignee of the instant application has discovered thatsulfur-oxide emissions can be controlled when burning viscous highsulfur containing hydrocarbon in water emulsions by the addition ofsulfur capturing additives to the emulsion composition. See U.S.Application Ser. Nos. 875,450 and 014,871.

Naturally, it would be highly desirable to develop a process for thepreparation of liquid fuels and a resultant liquid fuel which, uponcombustion, has a substantial reduction in sulfur oxide and nitrogenoxide emissions.

Accordingly, it is the principal object of the present invention toprovide an additive for addition to a hydrocarbon fuel which, uponcombustion of the fuel, acts as a sulfur and nitrogen capturing agent soas to substantially reduce the formation and emission of sulfur andnitrogen oxides.

It is a particular object of the present invention to provide a processas set forth above which is useful for hydrocarbon in water emulsions tobe burned as fuels.

Further objects and advantages of the present invention will appearhereinbelow.

SUMMARY OF THE INVENTION

The present invention relates to a process for the preparation of liquidfuels and the resulting fuel and, more particularly, a process thatallows a high sulfur and nitrogen containing fuel to be converted intoenergy by combustion with a substantial reduction in sulfur oxideemissions and nitrogen oxide emissions.

It is well known in the art to form oil in water emulsions either fromnaturally occurring bitumens or residual oil in order to facilitate theproduction and/or transportation of these viscous hydrocarbons. Typicalprocesses are disclosed in U.S. Pat. Nos. 3,380,531; 3,467,195;3,519,006; 3,943,954; 4,099,537; 4,108,193; 4,239,052 and 4,570,656. Inaddition to the foregoing, the prior art teaches that oil in wateremulsions formed from naturally occurring bitumens and/or residual oilscan be used as combustible fuels. See for example U.S. Pat. Nos.4,144,015; 4,378,230 and 4,618,348.

The present invention is drawn to a process for the preparation of aliquid fuel and the resulting fuel which, upon combustion, exhibits asubstantial reduction in sulfur oxide emissions and nitrogen oxideemissions. As noted above, the particular process is useful for fuels inthe form of hydrocarbon in water emulsions as disclosed in co-pendingApplication Ser. Nos. 014,871 and 875,450.

The process of the present invention comprises admixing a sulfur andnitrogen containing hydrocarbon (either hydrocarbon residual,hydrocarbon in water emulsion, or other suitable hydrocarbon) with awater soluble additive which acts as a capturing agent for sulfur andnitrogen upon combustion of the hydrocarbon as a fuel. In accordancewith the present invention, the water soluble additive consistsessentially of Na⁺, Fe⁺⁺ and an element X selected from group consistingof Mg⁺⁺, Ba⁺⁺, Ca⁺⁺, Li⁺, K⁺ and mixtures thereof wherein Na⁺ is presentin an amount of less than or equal to 40 wt.% based on the total weightof the water soluble additive, Fe⁺⁺ is present in an amount of greaterthan or equal to 0.4 wt.% based on the total weight of the water solubleadditive with the balance essentially element X wherein the ratio of Na⁺and Fe⁺⁺ is about between 7.5:1.0 to 100:1.0.

It has been found that the Fe⁺⁺ addition acts as a nitrogen capturingagent thereby reducing the amount of nitrogen oxide emissions. The Na⁺addition acts as a strong sulfur capturing agent for reducing sulfuroxide emissions; however, as the Na⁺ addition tends to be corrosive toboiler apparatuss the amount of Na⁺ in the additive should be limited.The remaining element X acts as a sulfur capturing agent and is used asa positive addition to complement the amount of Na⁺ in the additiveformulation. The overall additive formulation results in an effectivesulfur and nitrogen capturing additive which does not result in seriousdetrimental corrosion of boiler apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a bar graph showing the effect of additives on the reductionof SO₂ emissions.

FIG. 2 is a bar graph showing the effect of additives on the reductionof nitrogen oxide emissions.

DETAILED DESCRIPTION

In accordance with the present invention, the process of the presentinvention is drawn to the preparation and burning of a fuel formed froma naturally occurring bitumen or residual fuel oil product. One of thefuels for which the process is suitable is a bitumen crude oil having ahigh sulfur content such as those crudes typically found in the OrinocoBelt of Venezuela. The bitumen or residual oil has the followingchemical and physical properties: C wt.% of 78.2 to 85.5, H wt.% of 9.0to 10.8, O wt.% of 0.2 to 1.3, N wt.% of 0.50 to 0.70, S wt.% of 2 to4.5, Ash wt.% of 0.05 to 0.33, Vanadium, ppm of 50 to 1000, Nickel, ppmof 20 to 500, Iron, ppm of 5 to 60, Sodium, ppm of 30 to 200, Gravity,°API of 1.0 to 12.0, Viscosity (CST), 122° F. of 1,000 to 5,100,000,Viscosity (CST), 210° F. of 40 to 16,000, LHV (BTU/lb) of 15,000 to19,000, and Asphaltenes wt.% of 9.0 to 15.0. In accordance with onefeature of the present invention, a mixture comprising water and anemulsifying additive is mixed with a viscous hydrocarbon or residualfuel oil so as to from an oil in water emulsion. The characteristics ofthe oil in water emulsion and the formation of same are set forth in theabove-referenced co-pending applications which are incorporated hereinby reference. In accordance with the present invention, an additivewhich captures sulfur and nitrogen and prohibits the formation and theemission of sulfur oxides and nitrogen oxides during combustion of thehydrocarbon or hydrocarbon in water emulsion fuel is added to the fuelprior to the combustion of same. The water soluble additive for use inthe process of the present invention consists essentially of Na⁺, Fe⁺⁺and an element X selected from the group consisting of Mg⁺⁺, Ba⁺⁺, Ca⁺⁺,Li⁺, K⁺ and mixtures thereof. In accordance with the particular featureof the present invention the Na⁺ is present in an amount of less than orequal to 40 wt.% based on the total weight of the water solubleadditive. The Fe⁺⁺ is present in an amount of greater than or equal to0.4 wt.% based on the total weight of the water soluble additive. Thebalance of the water soluble additive is made up by the element X. Theratio of Na⁺ to Fe⁺⁺ in the additive ranges from about between 7.5:1.0to 100:1.0. The preferred formulation for the additive of the presentinvention used in the process of the present invention consistsessentially of Na⁺ in an amount of between 5 to 40 wt.% based on thetotal weight of the water soluble additive, Fe⁺⁺ in an amount of 0.4 to2.0 wt.% based on the total weight of the water soluble additive withthe balance essentially element X. It has been found that in order toobtain the desired emissions levels with respect to sulfur and nitrogenupon combustion of the fuel produced by the process of the presentinvention, the additive must be present in a molar ratio of additive tosulfur in the fuel of greater than or equal to 0.500 and preferablygreater than 0.750.

The advantages of the present invention will be clear from considerationof the following example.

EXAMPLE

In order to demonstate the effect of the additive of the presentinvention on the combustion characteristics of hydrocarbon fuelscontaining sulfur and nitrogen, ten additive formulations were prepared.The composition of the additive formulations are set forth hereinbelowin Table I.

                  TABLE I                                                         ______________________________________                                        Additive  Composition (wt. %)                                                 No.       Mg            Na      Fe                                            ______________________________________                                        1         80.5          18.9    0.65                                          2         62.2          37.3    0.50                                          3         67.4          32.1    0.40                                          4         67.4          32.1    0.43                                          5         79.5          19.2    1.28                                          6         61.9          37.1    0.99                                          7         83.0          15.9    1.06                                          8         67.2          32.0    0.86                                          9          2.7          97.3    0.00                                          10        98.8           0.00   1.2                                           ______________________________________                                    

Each of the additives were added to various oil in water emulsions forburning as natural fuels. The fuel characteristics operating conditionsand combustion characteristics for the fuels admixed with each additiveare set forth below in Tables II-XI.

                                      TABLE II                                    __________________________________________________________________________    ADDITIVE NO. 1                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                   EMULSION                                                                             #1     #2     #3     #4     #5                               __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 1/S                                                                            0      0.25   0.38   0.50   0.75   0.91                             (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  12029  11608  11203  10484  9852                             Bitumen, wt. %                                                                          74     68.5   66.1   63.8   59.7   56.1                             Water, wt. %                                                                            26     31.5   33.9   36.2   40.3   43.9                             Sulfur, wt. %                                                                           2.8    2.6    2.5    2.4    2.3    2.1                              OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   59.5   61.7   63.9   68.3   72.7                             Thermal Input                                                                           0.75   0.75   0.75   0.75   0.75   0.75                             (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151    149    150                              (°F.)                                                                  Steam/Fuel Ratio                                                                        0.30   0.30   0.30   0.30   0.30   0.30                             (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4    2.4    2.4                              (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     16     10     4      15     11                               CO.sub.2 (Vol %)                                                                        14.3   14.5   14.5   15.0   15.0   14.0                             O.sub.2 (Vol %)                                                                         3.0    3.0    2.9    2.8    2.9    2.9                              SO.sub.2 (ppm)                                                                          2100   1175   1000   700    350    200                              SO.sub.2 Reduction (%)                                                                  0      44.1   52.4   66.7   83.3   90.5                             NO.sub.x (ppm)                                                                          550    435    300    240    140    150                              NO.sub.x reduction (%)                                                                  0      20.9   45.5   56.4   74.6   72.7                             Combustion                                                                              99.8   99.9   99.9   99.9   99.9   99.9                             Efficiency (%)                                                                __________________________________________________________________________

                                      TABLE III                                   __________________________________________________________________________    ADDITIVE NO. 2                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                          EMULSION                                                                             #1     #2     #3     #4                                      __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 2/S                                                                            0      0.33   0.49   0.65   0.70                                    (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  12029  11608  11203  10484                                   Bitumen, wt. %                                                                          74     68.5   66.1   63.8   59.7                                    Water, wt. %                                                                            26     31.5   33.9   36.2   40.3                                    Sulfur, wt. %                                                                           2.8    2.6    2.5    2.4    2.3                                     OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   59.5   61.7   63.9   68.3                                    Thermal Input                                                                           0.75   0.75   0.75   0.75   0.75                                    (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151    149                                     (°F.)                                                                  Steam Fuel Ratio                                                                        0.30   0.30   0.30   0.30   0.30                                    (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4    2.4                                     (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     5      5      14     7                                       CO.sub.2 (Vol %)                                                                        14.3   14.0   14.0   14.0   14.0                                    O.sub.2 (Vol %)                                                                         3.0    3.0    2.9    3.0    3.2                                     SO.sub.2 (ppm)                                                                          2100   1150   750    380    280                                     SO.sub.2 Reduction (%)                                                                  0      45.2   64.3   81.2   86.7                                    NO.sub.x (ppm)                                                                          550    260    210    180    120                                     NO.sub.x reduction (%)                                                                  0      52.7   62.0   67.3   78.2                                    Combustion                                                                              99.8   99.9   99.9   99.9   99.9                                    Efficiency (%)                                                                __________________________________________________________________________     (*) Analyzer out of service                                              

                                      TABLE IV                                    __________________________________________________________________________    ADDITIVE NO. 3                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                          EMULSION                                                                             #1     #2     #3     #4                                      __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 3/S                                                                            0      0.30   0.45   0.60   0.90                                    (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  12029  11608  11203  10484                                   Bitumen, wt. %                                                                          74     68.5   66.1   63.8   59.7                                    Water, wt. %                                                                            26     31.5   33.9   36.2   40.3                                    Sulfur, wt. %                                                                           2.8    2.6    2.5    2.4    2.3                                     OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   59.5   61.7   63.9   68.3                                    Thermal Input                                                                           0.75   0.75   0.75   0.75   0.75                                    (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151    149                                     (°F.)                                                                  Steam Fuel Ratio                                                                        0.30   0.30   0.30   0.30   0.30                                    (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4    2.4                                     (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     16     26     6      5                                       CO.sub.2 (Vol %)                                                                        14.3   14.0   14.5   14.0   14.0                                    O.sub.2 (Vol %)                                                                         3.0    3.1    2.7    3.0    2.9                                     SO.sub.2 (ppm)                                                                          2100   1250   900    600    250                                     SO.sub.2 Reduction (%)                                                                  0      40.5   57.0   71.4   88.1                                    NO.sub.x (ppm)                                                                          550    310    210    115    (*)                                     NO.sub.x reduction (%)                                                                  0      44.0   62.0   79.1   (*)                                     Combustion                                                                              99.8   99.9   99.9   99.9   99.9                                    Efficiency (%)                                                                __________________________________________________________________________     (*) Analyzer out of service.                                             

                                      TABLE V                                     __________________________________________________________________________    ADDITIVE NO. 4                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                 EMULSION                                                                             #1     #2     #3                                             __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 4/S                                                                            0      0.38   0.56   0.75                                           (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  12029  11608  11203                                          Bitumen, wt. %                                                                          74     68.5   66.1   63.8                                           Water, wt. %                                                                            26     31.5   33.9   36.2                                           Sulfur, wt. %                                                                           2.8    2.6    2.5    2.4                                            OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   59.5   61.7   63.9                                           Thermal Input                                                                           0.75   0.75   0.75   0.75                                           (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151                                            (°F.)                                                                  Steam/Fuel Ratio                                                                        0.30   0.30   0.30   0.30                                           (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4                                            (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     14     14     13                                             CO.sub.2 (Vol %)                                                                        14.3   14.0   14.0   10.0                                           O.sub.2 (Vol %)                                                                         3.0    2.9    2.8    3.1                                            SO.sub.2 (ppm)                                                                          2100   1100   650    200                                            SO.sub.2 Reduction (%)                                                                  0      48.0   69.1   90.5                                           NO.sub.x (ppm)                                                                          550    280    240    140                                            NO.sub.x reduction (%)                                                                  0      49.0   56.4   74.6                                           Combustion                                                                              99.8   99.9   99.9   99.9                                           Efficiency (%)                                                                __________________________________________________________________________     (*) Analyzer out of service.                                             

                                      TABLE VI                                    __________________________________________________________________________    ADDITIVE NO. 5                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                          EMULSION                                                                             #1     #2     #3     #4                                      __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 5/S                                                                            0      0.15   0.38   0.50   0.75                                    (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  12029  11608  11203  10484                                   Bitumen, wt. %                                                                          74     68.5   66.1   63.8   59.7                                    Water, wt. %                                                                            26     31.5   33.9   36.2   40.3                                    Sulfur, wt. %                                                                           2.8    2.6    2.5    2.4    2.3                                     OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   59.5   61.7   63.9   68.3                                    Thermal Input                                                                           0.75   0.75   0.75   0.75   0.75                                    (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151    149                                     (°F.)                                                                  Steam/Fuel Ratio                                                                        0.30   0.30   0.30   0.30   0.30                                    (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4    2.4                                     (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    Co (ppm)  10     3      3      4      6                                       CO.sub.2 (Vol %)                                                                        14.3   14.0   14.0   14.5   14.5                                    O.sub.2 (Vol %)                                                                         3.0    3.0    3.0    3.0    3.0                                     SO.sub.2 (ppm)                                                                          2100   1100   725    680    350                                     SO.sub.2 Reduction (%)                                                                  0      47.6   65.5   67.6   83.3                                    NO.sub.x (ppm)                                                                          550    350    350    200    (*)                                     NO.sub.x reduction (%)                                                                  0      36.4   36.4   63.6   (*)                                     Combustion                                                                              99.8   99.9   99.9   99.9   99.9                                    Efficiency (%)                                                                __________________________________________________________________________     (*) Analyzer out of service.                                             

                                      TABLE VII                                   __________________________________________________________________________    ADDITIVE NO. 6                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                 EMULSION                                                                             #1     #2     #3                                             __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 6/S                                                                            0      0.49   0.65   0.70                                           (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  11608  11203  10484                                          Bitumen, wt. %                                                                          74     66.1   63.8   59.7                                           Water, wt. %                                                                            26     33.9   36.2   40.3                                           Sulfur, wt. %                                                                           2.8    2.5    2.4    2.3                                            OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   61.7   63.9   68.3                                           Thermal Input                                                                           0.75   0.75   0.75   0.75                                           (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151                                            (°F.)                                                                  Steam/Fuel Ratio                                                                        0.30   0.30   0.30   0.30                                           (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4                                            (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     4      10     15                                             CO.sub.2 (Vol %)                                                                        14.3   15.0   15.0   15.0                                           O.sub.2 (Vol %)                                                                         3.0    2.7    3.0    3.0                                            SO.sub.2 (ppm)                                                                          2100   650    350    250                                            SO.sub.2 Reduction (%)                                                                  0      69.0   83.3   88.1                                           NO.sub.x (ppm)                                                                          550    320    140    140                                            NO.sub.x reduction (%)                                                                  0      41.8   74.5   74.5                                           Combustion                                                                              99.8   99.9   99.9   99.9                                           Efficiency (%)                                                                __________________________________________________________________________

                                      TABLE VIII                                  __________________________________________________________________________    ADDITIVE NO. 7                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                 EMULSION                                                                             #1     #2     #3                                             __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 7/S                                                                            0      0.45   0.60   0.90                                           (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  11608  11203  10484                                          Bitumen, wt. %                                                                          74     66.1   63.8   59.7                                           Water, wt. %                                                                            26     33.9   36.2   40.3                                           Sulfur, wt. %                                                                           2.8    2.5    2.4    2.3                                            OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   61.7   63.9   68.3                                           Thermal Input                                                                           0.75   0.75   0.75   0.75                                           (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151                                            (°F.)                                                                  Steam/Fuel Ratio                                                                        0.30   0.30   0.30   0.30                                           (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4                                            (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     10     6      8                                              CO.sub.2 (Vol %)                                                                        14.3   15.0   15.0   14.5                                           O.sub.2 (Vol %)                                                                         3.0    3.0    2.9    2.8                                            SO.sub.2 (ppm)                                                                          2100   800    550    200                                            SO.sub.2 Reduction (%)                                                                  0      61.9   73.8   90.5                                           NO.sub.x (ppm)                                                                          550    260    150    62                                             NO.sub.x reduction (%)                                                                  0      52.7   72.7   88.7                                           Combustion                                                                              99.8   99.9   99.9   99.9                                           Efficiency (%)                                                                __________________________________________________________________________

                                      TABLE IX                                    __________________________________________________________________________    ADDITIVE NO. 8                                                                          BASELINE                                                                             EMULSION                                                                             EMULSION                                                                             EMULSION                                                 EMULSION                                                                             #1     #2     #3                                             __________________________________________________________________________    FUEL CHARACTERISTICS                                                          Additive 8/S                                                                            0      0.56   0.75   0.93                                           (Molar Ratio)                                                                 LHV (BTU/lb)                                                                            12995  11608  11203  10484                                          Bitumen, wt. %                                                                          74     66.1   63.8   59.7                                           Water, wt. %                                                                            26     33.9   36.2   40.3                                           Sulfur, wt. %                                                                           2.8    2.5    2.4    2.3                                            OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                        55.1   61.7   63.9   68.3                                           Thermal Input                                                                           0.75   0.75   0.75   0.75                                           (MMBTU/h)                                                                     Fuel Temperature                                                                        149    150    149    151                                            (°F.)                                                                  Steam/Fuel Ratio                                                                        0.30   0.30   0.30   0.30                                           (w/w)                                                                         Steam Pressure                                                                          2.4    2.4    2.4    2.4                                            (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)  10     30     7      10                                             CO.sub.2 (Vol %)                                                                        14.3   14.0   14.0   14.0                                           O.sub.2 (Vol %)                                                                         3.0    3.0    2.9    3.0                                            SO.sub.2 (ppm)                                                                          2100   550    180    75                                             SO.sub.2 Reduction (%)                                                                  0      73.8   91.4   96.4                                           NO.sub.x (ppm)                                                                          550    230    150    100                                            NO.sub.x reduction (%)                                                                  0      58.2   67.3   81.8                                           Combustion                                                                              99.8   99.9   99.9   99.9                                           Efficiency (%)                                                                __________________________________________________________________________

                  TABLE X                                                         ______________________________________                                        ADDITIVE NO. 9                                                                          BASELINE EMULSION   EMULSION                                                  EMULSION #1         #2                                              ______________________________________                                        FUEL CHARACTERISTICS                                                          Additive 9/S                                                                              0          0.011      0.097                                       (Molar Ratio)                                                                 LHV (BTU/lb)                                                                              13337      13277      12900                                       Bitumn, wt. %                                                                             78         78         70                                          Water, wt. %                                                                              22         22         30                                          Sulfur, wt. %                                                                             3.0        3.0        2.7                                         OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                          60.0       60.0       66.7                                        Thermal Input                                                                             0.82       0.82       0.82                                        (MMBTU/h)                                                                     Fuel Temperature                                                                          154        154        154                                         (°F.)                                                                  Steam/Fuel Ratio                                                                          0.30       0.30       0.30                                        (w/w)                                                                         Steam Pressure                                                                            2.4        2.4        2.4                                         (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO (ppm)    36         27         20                                          CO.sub.2 (Vol %)                                                                          13.0       12.9       12.9                                        O.sub.2 (Vol %)                                                                           3.0        2.9        3.0                                         SO.sub.2 (ppm)                                                                            2347       1775       165                                         SO.sub.2 Reduction (%)                                                                    0          24.4       93.1                                        NO.sub.x (ppm)                                                                            450        498        434                                         NO.sub.x reduction (%)                                                                    0          (9.7)      3.5                                         Combustion  99.8       99.8       99.9                                        Efficiency (%)                                                                ______________________________________                                    

                  TABLE XI                                                        ______________________________________                                        ADDITIVE NO. 10                                                                         BASELINE EMULSION   EMULSION                                                  EMULSION #1         #2                                              ______________________________________                                        FUEL CHARACTERISTICS                                                          Additive 10/S                                                                             0          0.30       0.78                                        (Molar Ratio)                                                                 LHV (BTU/lb)                                                                              13086      12742      10845                                       Bitumen, wt. %                                                                            76         74         63                                          Water, wt. %                                                                              24         26         37                                          Sulfur, wt. %                                                                             2.9        2.8        2.4                                         OPERATING CONDITIONS                                                          Feed Rate (lb/h)                                                                          55.1       56.2       66.0                                        Thermal Input                                                                             0.72       0.72       0.72                                        (MMBTU/h)                                                                     Fuel Temperature                                                                          149        149        149                                         (°F.)                                                                  Steam/Fuel Ratio                                                                          0.30       0.30       0.30                                        (w/w)                                                                         Steam Pressure                                                                            2.4        2.4        2.4                                         (bar)                                                                         COMBUSTION CHARACTERISTICS                                                    CO.sub.2 (Vol %)                                                                          13.5       14.0       13.2                                        O.sub.2 (Vol %)                                                                           3.0        2.9        3.0                                         SO.sub.2 (ppm)                                                                            2357       1250       167                                         SO.sub.2 Reduction (%)                                                                    0          47.0       92.9                                        NO.sub.x (ppm)                                                                            500        430        218                                         NO.sub.x reduction (%)                                                                    0          14.0       56.4                                        Combustion  99.8       99.9       99.8                                        Efficiency (%)                                                                ______________________________________                                    

As can be seen from the foregoing tables, Fe⁺⁺ additions to the additivehas a marked effect on reducing nitrogen oxide emissions upon combustionof the fuel. The comparative effect of Fe⁺⁺ on nitrogen oxide additionscompared to the effect obtained from Na⁺ and element X (in this casemagnesium) is set forth in FIG. 2. Likewise, as can be seen from theforegoing tables II-XI, Na⁺ has a marked effect on reducing sulfur oxideemissions when compared to iorn and the element X addition. See FIG. 1.

In addition to the foregoing, it is seen from the foregoing combustiondata that the molar ratio of additive to sulfur in the hydrocarbon fuelhas an effect on the reduction of SO₂ and nitrogen oxide with reductionsof greater than 80% in SO₂ being obtained at molar ratios of additive tosulfur of greater than 0.500 and preferably greater than 0.750.

In addition to the foregoing, the combustion ash characterisitics forEmulsion 5 of Table II and Emulsion 2 of Table IX were analyzed. Thecompositions are set forth below in Table XII.

                  TABLE XII                                                       ______________________________________                                        ASH CHARACTERISTICS                                                                                  Melting                                                                       Point                                                  Additive Compound      (°F.)                                                                           Observations                                  ______________________________________                                        TABLE X  3Na.sub.2 O.V.sub.2 O.sub.5                                                                 1562     POTENTIALLY                                   ADDITIVE 2Na.sub.2 O.V.sub.2 O.sub.5                                                                 1184     CORROSIVE                                     9        Na.sub.2 O.V.sub.2 O.sub.5                                                                  1166                                                            Na.sub.2 SO.sub.4                                                                           1616                                                            Na.sub.2 O.V.sub.2 O.sub.4.5V.sub.2 O.sub.5                                                 1157                                                   TABLE II MgSO.sub.4    2055     NON-                                          ADDITIVE 3MgO.V.sub.2 O.sub.5                                                                        2174     CORROSIVE                                     1        NiSO.sub.4    1544                                                            MgO           2642                                                            Na.sub.2 SO.sub.4                                                                           1616                                                   ______________________________________                                    

The ash composition employing additive 9 (a high sodium additivecomposition) indicates that the ash is potentially corrosive andtherefore undesirable. Accordingly, the ideal additive composition inorder to minimize sulfur oxide and nitrogen oxide emissions and reducethe potential for corrosion comprises Na⁺ in an amount of about 5 to 40wt.%, Fe⁺⁺ in an amount of between 0.4 to 2.0 wt.% with the balanceessentially element X.

This invention may be embodied in other forms or carried out in otherways without departing from the spirit or essential characteristicsthereof. The present embodiment is therefore to be considered as in allrespects illustrative and not restrictive, the scope of the inventionbeing indicated by the appended claims, and all changes which comewithin the meaning and range of equivalency are intended to be embracedtherein.

What is claimed is:
 1. A process for controlling sulfur oxide andnitrogen oxide formation and emissions when burning by forming acombustible fuel prepared from a bitumen or residual fuel oilhydrocarbon containing sulfur and nitrogen comprising:(a) mixing asulfur and nitrogen containing hydrocarbon with a water soluble additivewherein said water soluble additive consist essentially of Na⁺, Fe⁺⁺ andan element X selected from the group consisting of Mg⁺⁺, Ba⁺⁺, Ca⁺⁺,Li⁺, K⁺ and mixtures thereof wherein Na⁺ is present in an amount of lessthan or equal to 40 wt.%, Fe⁺⁺ is present in an amount of greater thanor equal to 0.4 wt.%, balance essentially X wherein the ratio of Na⁺ toFe⁺⁺ is about between 7.5:1.0 to 100:1.0 and the molar ratio of additiveto sulfur in said hydrocarbon is greater than about 0.500.
 2. A processaccording to claim 1 wherein Na⁺ is present in an amount of between 15to 40 wt.%, Fe⁺⁺ is present in an amount of 0.4 to 2.0 wt.%, balanceessentially X.
 3. A process according to claim 1 wherein the molar ratioof additive to sulfur is greater than 0.750.
 4. A process according toclaim 1 wherein said hydrocarbon is a hydrocarbon in water emulsionformed by admixing a mixture of a sulfur containing hydrocarbon in waterwith an emulsifier wherein said emulsion has a water content of aboutbetween 5 to 40 volume percent.
 5. A bitumen or residual fuel oilhydrocarbon combustible fuel comprising a sulfur and nitrogen containinghydrocarbon and a water soluble sulfur and nitrogen capturing additivewherein said water soluble additive consists essentially of Na⁺, Fe⁺⁺and an element X selected from the group consisting of Mg⁺⁺, Ba⁺⁺, Ca⁺⁺,Li⁺, K⁺ and mixtures thereof wherein Na⁺ is present in an amount of lessthan or equal to 40 wt.%, Fe⁺⁺ is present in an amount of greater thanor equal to 0.4 wt.%, balance essentially X wherein the ratio of Na⁺ toFe⁺⁺ is about between 7.5:1.0 to 100:1.0 and the molar ratio of additiveto sulfur is greater than 0.500.
 6. A hydrocarbon combustible fuelaccording to claim 5 wherein Na⁺ is present in an amount of between 15to 40 wt.%, Fe⁺⁺ is present in an amount of 0.4 to 2.0 wt.%, balanceessentially X.
 7. A hydrocarbon combustible fuel according to claim 5wherein the molar ratio of additive to sulfur is greater than 0.750.